1. Field of the Invention
The present invention relates to an image forming apparatus for forming an image on a long sheet.
2. Description of Related Art
Conventionally, image forming apparatuses (such as a printer, a copier, and a facsimile machine) which can form an image on a long sheet such as a roll sheet and a continuous sheet (continuous form paper) are known. For example, an electrophotographic image forming apparatus is configured to irradiate (expose) a uniformly-charged photoconductor (for example, a photoconductor drum) with (to) laser light based on image data to form an electrostatic latent image on the surface of the photoconductor. The electrostatic latent image is then visualized by supplying toner from a developing device to the photoconductor on which the electrostatic latent image is formed, whereby a toner image is formed. Further, the toner image is directly or indirectly transferred to a sheet through an intermediate transfer belt, followed by heating and pressurization for fixing at a fixing section, whereby an image is formed on the sheet.
In general, the interior of an image forming apparatus is contaminated and damaged by paper dust and preprinted ink component, and therefore cleaning of the sheet feeding path is required. In particular, when an image is formed on a tack roll sheet (a roll sheet including a surface base material, adhesive, and a release sheet) used for making labels, adhesive that comes off from the sheet adheres to parts (for example, a conveyance roller and a conveyance guide disposed in the sheet width direction) that make contact with an end portion of the sheet, and therefore it is necessary to frequently clean up the sheet feeding path.
When the sheet feeding path is cleaned, the sheet feeding path is exposed by widely exposing the exterior portion of the image forming apparatus, or by pulling a sheet conveyance section including a conveyance roller section and a conveyance guide part in the sheet width direction from a front door of the image forming apparatus, for example (see, for example, Japanese Patent Application Laid-Open No. 2007-172014).
However, when the interior of the apparatus is exposed by widely exposing the exterior of the image forming apparatus to perform cleaning, a long sheet still presents in the sheet feeding path, and therefore the cleaning of the parts under the long sheet cannot be performed. In addition, since the cleaning has to be performed while avoiding the structural parts, it is difficult to ensure a sufficient space for the cleaning. Furthermore, in electrophotographic image forming apparatuses having complicated internal structures, parts which can be exposed are limited, and therefore the workability is poor.
In the case where cleaning is performed by pulling out the sheet conveyance section in the sheet width direction, the sheet conveyance section cannot be pulled when the long sheet exists in the feeding path since the long sheet is torn if the sheet conveyance section is pulled in the state where the long sheet exists in the feeding path. For this reason, the long sheet has to be removed from the sheet feeding path to pull out the sheet conveyance section, and thus removal of the long sheet and resupply of the sheet after the cleaning are required, and as a result, the cleaning operation is complicated.